This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Nanomedicine utilizes nanoscale materials and principles to effect medical intervention at the molecular scale with the goal of curing diseases or repairing tissues. Drug delivery is arguably one of the most important and promising areas in nanomedicine. Amongst the many recently developed drug carriers, inorganic nanomaterials, in particular amorphous mesoporous silica nanoparticles, are particularly attractive due to their biocompatibility combined with high surface area and pore volume and uniform, tunable pore diameters and surface chemistries. Most drug loading schemes rely on electrostatic interactions. For example, pure silica is negatively charged at neutral or physiological pH and strongly adsorbs positively charged drugs. Such a drug loading mechanism, however, is susceptible to pre-mature drug release induced by displacement by other molecules or ions in the body fluid. The samples will mainly be mesoporous silica nanoparticle supported phospholipid bilayers. We aim to use cryo-EM to observe the supported bilayer or multilayer structures are a function of lipid charge and fluidity. This characterization will be beneficial for the design of the nanoparticles.